Belt installation tool

ABSTRACT

The invention comprises a belt installation tool for installing a flexible belt on a pulley. On one side, the radius of the tool is substantially equivalent to the radius of a pulley flange. The bearing surface on this side of the tool stretches the belt and guides the belt onto the pulley. To avoid damaging the belt, the radius of the tool and the pulley flange should be substantially equal over a substantial length of the pulley. Centric to this radius, a hole is provided to accommodate a single-end socket that projects through the tool. The socket engages a crankshaft bolt, hence, the belt installation tool is centered on the pulley along the socket centerline. The tool and pulley are then turned with a ratchet attached to the socket. The tool comprises a belt bearing surface having a variable radius that allows a belt to be stretched to a proper radius without abrupt radius changes, which could damage a belt. The belt is moved axially from the tool into the pulley grooves by a leaderblock, which is provided at the tool radius on the bearing surface adjacent to the pulley grooves. By turning the tool about the crankshaft the leaderblock guides the belt flank, causing it to move into a pulley groove. The leaderblock comprises a lip to further hold the tool on a pulley rim.

REFERENCE TO RELATED APPLICATIONS

[0001] This divisional application claims priority from U.S. patentapplication Ser. No. 09/705,173 filed Nov. 2, 2000.

FIELD OF THE INVENTION

[0002] The invention relates to belt installation tools and moreparticularly to a belt installation tool having an eccentric rampsurface whereby a flexible drive belt is stretched and progressivelyguided into a pulley groove.

BACKGROUND OF THE INVENTION

[0003] Belt drive systems comprise a significant and widely used form ofmechanical power transmission. Generally a belt runs between two or morepulleys, more particularly a driver and driven pulley.

[0004] In order to efficiently transmit power between the pulleys thebelt is installed with a predetermined preload or tension. The amount oftension is generally a function of the horsepower and torquerequirements of the drive. An increased horsepower or torque requirementwill generally require a commensurate increase in the tension of thebelt.

[0005] In order to achieve the proper tension, one or more of thepulleys is loosened so the shaft or shafts can be moved to allow a slackcondition in the belt. Then, the belt is looped over the pulleys. Theloosened pulley or pulleys are then pulled or tightened in apredetermined position, resulting in a tension in the belt. This processrequires the pulley(s) to be mechanically adjusted to properly tensionthe belt.

[0006] Belts may be installed on pulley systems using other methods. Forsystems with an automatic tensioning device the tensioner is loaded, thebelt is placed in an operating position, and the tensioner is releasedto its operational location. For systems without a tensioner, belts arewrapped around the pulleys and then a pulley is tightened to its finallocation by a bracket or similar devices.

[0007] Another method of installing a belt involves use of a tool thatpresses the belt into a pulley groove without the need for mechanicallyadjusting the pulleys. The tool is used adjacent to a pulley. Itstretches the belt while laterally forcing it into a pulley groove.

[0008] Representative of the prior art is European Patent No. 0 831 247B1 to Hutchinson which discloses a tool having a radial thrust arearesting against a girth of the pulley, keeping a belt away from a pulleyuntil it reaches a plane spaced from a pulley surface.

[0009] Also representative of the art is U.S. Pat. No. 4,193,310 (1980)to Boyer et al. which discloses a pulley having a diverging meansextending radially and laterally from the rim for engaging and seatingthe belt on the pulley rim. This invention does not comprise a bearingsurface for gradually entraining a belt on a pulley, instead having apeg that abruptly bends the belt into the pulley groove.

[0010] The prior art apparatus forces a belt to bend over small radiusportions of the tool, causing high stress concentrations that damage thebelt during installation. Further, high lateral loads damage thesidewalls of the belt. Finally, the transverse motion of the belt as itmoves into the pulley groove may also damage the belt.

[0011] What is needed is a belt installation tool having an eccentricbelt bearing surface having a variable radius and a portion of whichsubstantially aligns with a pulley groove. What is needed is a beltinstallation tool having a hole for receiving a socket for engaging apulley bolt. What is needed is a belt installation tool wherein the beltbearing surface has a radius substantially equal to a pulley radius.What is needed is a belt installation tool having a surface normal tothe belt bearing surface for urging a belt into a pulley groove. Thepresent invention meets these needs.

SUMMARY OF THE INVENTION

[0012] The primary aspect of the invention is to provide a beltinstallation tool having an eccentric belt bearing surface having avariable radius and a portion of which substantially aligns with apulley groove.

[0013] Another aspect of the invention is to provide a belt installationtool having a hole for receiving a socket for engaging a pulley bolt.

[0014] Another aspect of the invention is to provide a belt installationtool wherein the belt bearing surface has a radius substantially equalto a pulley radius.

[0015] Another aspect of the invention is to provide belt installationtool having a surface normal to the belt bearing surface for urging abelt into a pulley groove.

[0016] Other aspects of the invention will be pointed out or madeobvious by the following description of the invention and theaccompanying drawings.

[0017] The invention comprises a belt installation tool for installing aflexible belt on a pulley. The tool comprises an eccentric belt bearingsurface. On one side, the radius of the tool is substantially equivalentto the radius measured from a pulley center to a pulley rim or flange.The bearing surface on this side of the tool stretches the belt andguides the belt into a pulley groove. To avoid damaging the belt theradius of the tool belt bearing surface and the pulley flange should besubstantially equal over a substantial length of the tool. Centric tothe tool radius a hole is provided to accommodate a single-end socketthat projects through the tool to engage a crankshaft or pulley bolt,hence, the belt installation tool is centered to the pulley along thesocket centerline. The tool and pulley are then turned with a ratchetattached to the socket. The belt is moved axially from the tool into thepulley grooves by a leaderblock, which is provided at the maximum toolradius on the belt bearing surface adjacent to the pulley grooves. Byturning the tool about the crankshaft the leaderblock presses the beltflank causing it to move it into the pulley grooves. The leaderblockalso comprises a lip to engage a pulley rim.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which are incorporated in and form apart of the specification, illustrate preferred embodiments of thepresent invention, and together with a description, serve to explain theprinciples of the invention.

[0019]FIG. 1 is a rear perspective view of the belt installation tool.

[0020]FIG. 2 is a front perspective view of the tool.

[0021]FIG. 3 is a perspective view of the mating surface of theleaderblock.

[0022]FIG. 4 is a perspective view of the tool in use.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0023]FIG. 1 is a front perspective view of the belt installation tool.Tool 10 comprises body 11. Body 11 comprises belt bearing surface 12 andbelt bearing surface 13. Surface 12 describes radius R12 and surface 13describes radius R13. Radius R12 is centered at the center of hole 15.Radius R13 is less than radius R12.

[0024] Hole 15 in body 11 has a diameter D15. Ridge 16, which provides abearing surface for placing the tool against a pulley, encircles hole15. Slot 17 is cut on a radial from hole 15. Slot 17 has width G. Hole18 traverses slot 17. Hole 18 is threaded to accommodate a fastener 19(not shown). A ratchet socket (not shown) is inserted into hole 15. Thenfastener 19 is tightened, compressing slot 17 and thereby hole 15 aboutthe socket, firmly affixing the tool to the socket.

[0025] Edge 14 extends about an outer portion of the tool. Edge 14 is anormal surface which prevents a belt from slipping from the tool when abelt is loosely looped on the bearing surface.

[0026] Block 50 is affixed to surface 12 by fasteners, such as threadedfasteners (not shown), known in the art. The fasteners are insertedthrough slots 51. Block 50 comprises lip 52 which engages a rim of apulley along with slot 53. Lip 52 and slot 53 each describe a radiussubstantially corresponding to radius R12, although a preciseequivalence is not required for proper operation of the tool.

[0027] In operation, a socket S, having a size compatible with a pulleyshaft bolt, is inserted through hole 15. Fastener 19 is tightened,thereby affixing tool 10 to socket S. Lip 52 is engaged with a pulleyrim. Socket S is then engaged with a crankshaft or pulley bolt C. A beltB is loosely looped about the tool on surfaces 30, 31. A ratchet isconnected to the socket S. Tool 10 is turned with the ratchet, bringingbelt B into contact with surface 13. As the ratchet is turned further,tool 10 turns under belt B until belt B engages surface 12. Since radiusR12 is substantially equivalent to a radius of a pulley, the belt whenit engages surface 12 will be substantially adjacent to the pulleygrooves. As the tool is turned further, the belt engages edge 55 ofleaderblock 50. Engagement with edge 55 urges a belt B into the pulleygrooves. As the tool is turned further, the belt trains into the pulleygrooves. Once the tool completes a full turn, the belt is fully engagedin the pulley groove and disengaged from the tool. The tool is thenremoved from the crankshaft bolt.

[0028]FIG. 2 is a front perspective view of the tool. Hole 15 extendsfrom the front of the tool to the back as described in FIG. 1.Leaderblock 50 is shown mounted to surface 12.

[0029]FIG. 3 is a perspective view of the mating surface of theleaderblock. Slots 51 extend through block 50. Lip 52 and slot 53 engagea rim of a pulley. Fasteners, such as threaded fasteners (not shown),extend through slots 51 to affix the block to surface 12. Slot 53comprises a slight radius centered on a center axis of hole 15 toconform to the curve of the pulley rim. In operation, lip 52 engages therim of a pulley while the socket extending through hole 15 engages ashaft bolt, thereby firmly attaching the tool to a pulley for installinga belt. Block surface 54 and block surface 56 comprise ends of block 50.

[0030]FIG. 4 is a perspective view of the tool in use. Tool 10 is shownwith a socket tool T engaged through hole 15. Socket S engages a pulleybolt (not shown) . Initially, belt B is loosely engaged with surfaces 12and 13 with a portion engaging the pulley P as shown. As the tool andpulley are turned in direction M by a user, belt B is gently urged intoa pulley groove by interaction with block 50. The belt fully engages apulley groove upon completion of one revolution of the pulley and tool.

[0031] Although a single form of the invention has been describedherein, it will be obvious to those skilled in the art that variationsmay be made in the construction and relation of parts without departingfrom the spirit and scope of the invention described herein.

I claim:
 1. A belt installation tool comprising: a body describing ahole and having a belt bearing surface; a block extending from the beltbearing surface, the block having a lip for engaging a pulley rim; andthe hole alignable with a pulley shaft bolt such that a portion of thebelt bearing surface is adjacent to a pulley groove.
 2. The beltinstallation tool as in claim 1, wherein; the block affixed to the beltbearing surface at a maximum radius and having a belt urging surfaceextending substantially normal to the belt bearing surface; and the beltbearing surface further comprises a variable radius, the radiusdecreasing in a direction away from the block to a minimum radiusadjacent to the hole.
 3. The belt installation tool as in claim 2further comprising: a surface substantially normal to the belt bearingsurface, the surface extending from an edge of the belt bearing surfaceopposite a pulley rim.
 4. The belt installation tool as in claim 3,further comprising: a slot having a width extending radially from thehole whereby a fastener is used to compress the groove width and therebydecrease the radius of the hole, whereby the tool grips a shaft.
 5. Thebelt installation tool as in claim 4, wherein the maximum radius issubstantially equivalent to the radius of a pulley rim.
 6. A beltinstallation tool comprising: a body describing a hole and having a beltbearing surface; a block extending from the belt bearing surface, theblock having a lip for engaging a pulley rim; and the hole coaxiallyaligned with a pulley shaft bolt such that a portion of the belt bearingsurface is adjacent to a pulley groove.
 7. The belt installation tool asin claim 6, wherein; the block affixed to the belt bearing surface at amaximum radius and having a belt urging surface extending substantiallynormal to the belt bearing surface; and the belt bearing surface furthercomprises a variable radius, the radius decreasing in a direction awayfrom the block to a minimum radius adjacent to the hole.
 8. The beltinstallation tool as in claim 7 further comprising: a surfacesubstantially normal to the belt bearing surface, the surface extendingfrom an edge of the belt bearing surface opposite a pulley rim.
 9. Thebelt installation tool as in claim 8, further comprising: a slot havinga width extending radially from the hole whereby a fastener is used tocompress the groove width and thereby decrease the radius of the hole,whereby the tool grips a shaft.
 10. The belt installation tool as inclaim 9, wherein the maximum radius is substantially equivalent to theradius of a pulley rim.